Expanded trinucleotide repeats in the TBP/SCA17 gene mapped to chromosome 6q27 are associated with schizophrenia
Received 13 April 2005; received in revised form 21 June 2005; accepted 21 June 2005.
Abstract
Schizophrenia has a complex and non-Mendelian mode of inheritance. Recently, trinucleotide repeat (TNR)-containing genes have been considered as the candidate genes predisposing to schizophrenia. The purpose of this study was to determine whether a genetic association could be observed between schizophrenia and the TNR polymorphisms within the KLHL1AS/SCA8, PPP2R2B/SCA12, and TBP/SCA17 genes. We studied 100 unrelated schizophrenia patients and 124 controls without evident neurodegenerative or psychiatric disorders. The overall allele frequency distributions of the KLHL1AS/SCA8 and PPP2R2B/SCA12 genes were not significantly different between the schizophrenic patients and the control subjects (P>0.05). The allele frequency distribution in the schizophrenic patients was significantly different from that in the controls at the TBP/SCA17 gene (P=0.0149), with an increased frequency of 36 repeats in the patients and two patients carrying 45 TNR expansions were identified. TBP/SCA17 is the TATA box binding protein gene mapped to chromosome 6q27. The study suggests that TNR expansions of the TBP/SCA17 gene may contribute to the genetic risk of schizophrenia in rare cases.
aDepartment of Neurology, Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, Taipei 105, Taiwan
bDepartment of Psychiatry, China Medical University Hospital, No. 2, Yuh-Der Road, Taichung 404, Taiwan
cDepartment of Life Science, National Taiwan Normal University, 88 Ting-Chou Road, Section 4, Taipei 116, Taiwan
dNeurological Institute, Taipei Veterans General Hospital and School of Medicine, National Yang-Ming University, Taipei 112, Taiwan
Corresponding authors. G.-J. Lee-Chen is to be contacted at Tel.: +886 2 29336875; fax: +886 2 29312904. H.-Y. Lane is to be contacted at Tel.: +886 4 22052121; fax: +886 4 22361042.
ABSTRACT